Answer: During Photosynthesis, CO2 is reduced. This means that :
Explanation: During Photosynthesis, plants take in CO2 for production of food (glucose and other materials) in the cell for growth and development of the plant. CO2 levels aren't reduced as the balance chain between plants and animals for exchange of gases prevents it from happening. In turn, plants produce O2 for animals so that thy can live and produce CO2 for the plants.
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